Is it safe to use aluminum coil in jockey boxes even if the tube is firstly boiled to create that protective dark layer on it?
And what is the frequency that is necessary to make and keep it with that protective dark layer?
Aluminium was discontinued for use in casks and kegs here in the UK in the due to it slowly being dissolved by the beer when the protective epoxy liners got damaged. A layer of oxide will not protect your aluminium from being corroded by the beer, I would use stainless or plastic.
I wouldn't be worried about using aluminium, personally, but be VERY careful with your choice of cleaners. Most especially, don't try to use caustic. If you're at all worried, I would recommend finding a stainless coil, or using some normal beerline. Or even a cooling plate.
As a side concern, do you know where the coil has been? What has it been used for in the past, if anything?
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